Number of unique items in a list in Python

Question

If I have a set of items in a list say:

MyList = ["a", "b", "c", "c", "b"]

And I want to get the count of the total number of unique items (in this case 3)

I figure it needs to be some variant on len(myList) but I'm not sure how to eliminate the duplicates?

I'm not sure how to answer the part about it being duplicate... it's true, but for some reason I didn't find it with a google search, and I think my version of the question is a bit clearer (but I'm ok with this being deleted if need be as I got my answer) — Mike, Mar 15 '15 at 20:44

score 6 · Answer 1 · answered Mar 15 '15 at 20:35

6

You can convert your list to a set which is guaranteed to have unique items:

MyList = ["a", "b", "c", "c", "b"]
print len(set(MyList))

result:

answered Mar 15 '15 at 20:35

Selcuk

1 Answers1